Some info on that, some people get confused with the difference.
When can I use the ®
Many people are confused on this subject and use "TM" or “®” incorrectly with their brand or logo.
When you use your trademark, logo or brand you can claim rights to it and you may use the “TM” (trademark) or “SM” (service mark) designation to alert the world to your claim of ownership of the brand. You may do so whether you have filed an application with the United States Patent and Trademark Office (USPTO).
However, you may only use the federal registration symbol “®” after the USPTO actually registers a mark, and not while an application is pending.
what about ©
Copyright © laws protect ownership of things like music, writing, artwork, photographs, and other "original works of authorship." Copyright protection is automatic and may last for over 100 years. However, not everything can be copyrighted, and some copyrights expired prior to 1976 laws. The "circle-c" mark has been "optional" since the 1970s, but is properly used with a date and identification of the author/owner. Under the Digital Millennium Copyright Act, it is a federal crime to remove or alter a copyright notice when you're making copies, regardless of whether the copies are lawful or not.
Trademark laws protect "words, names, symbols, sounds, or colors that distinguish goods and services from those manufactured or sold by others and to indicate the source of the goods. Trademarks, unlike patents, can be renewed forever as long as they are being used in commerce." Unregistered trademarks are a bit harder to enforce than registered, but last as long as they are being used. Trademarks may be registered in states or countries or both.
The (TM) symbols for TM and SM are completely optional and require no registration. However, there are advantages to having a state or federal trademark registration, including the fact that it will tell others when you first used your brand, which can be important in priority disputes. Valuable marks justify getting professional advice.
So in short anything you create that is an original is already copyright. An Old fashion way of copyrighting your work is after you draw it, place it in a sealed envelope and mail it to yourself. Date and signature.
You apply for a trademark and pay to have it certified. What this does is register your work with the USPTO and if anyone uses the same thing or name they will send them a letter saying cease and desist or legal action can and will be taken.
Getting a Trademark cost about $150-250 I think. Can't remember how much i paid.
You can use Legalzoom they are very helpful in the process.
But if you are serious getting a TM is highly rec. in this business.